there are always cheaper places, but it always comes down to the quality level you want. frankly i hate it when i hear "it's cheaper elsewhere" as cheaper generally means "not as good" so if someone say s where can i get a cheap job? then point them in the direction of a local powdercoater, if you want a show bike quality paint job go to a specialist.
personally i'd only use Argos, Bob Jackson, and TJC, that's it, i choose which to use based on the job i want, they are all good quality so then it comes down to the price for the job i want, single colour with no stickers i find Bob is cheapest, best stickers and paint i think TJC, Argos is in the middle but always busier and your best off supplying stickers yourself (from Gil_m) and they tend to take longer because of how busy they are.